Lexmex

You don't need to change them out every year. I did a test, twice, and showed the fluid was just fine after a year. You can do what you wish as far as going non-synthetic, but I personally wouldn't put anything but a synthetic in my RX300, and that's just because of my Mexican experiences. Plus, I don't know that the cost is really that much of an issue for something that minimally, might get changed out every 30K miles. Gear oil is one of those things that can last a while. I am pretty sure that from the time I got my RX300 used at about 42K until about 100K or so when I first changed out the gear oils, Lexus never did this, but the vehicle still worked okay. But after changing out the gear oil at that point, I did notice an improvement in 2nd to 3rd gear (which I felt personally in the last 75 meters of so of 1/4 mile racing).

UNOHOO

iTrader: (3)

i have 212k miles on it, 99 awd btw, have no clue if it had been done before, i bought the car at 150-160k miles and just did it for the first time, the one that was in there was a wire screen, new one was paper or cloth, didnt look that closely, same exact shape as the one pictured in tunedrx300's diy, this is my first car that i actually started doin all the work on it myself and no place i took it would do a tranny flush cause they didnt have the right atf, then i found you guys and enlisted my gf to help me work on my car myself

bob2200

Thanks, that's good information. Maybe I'll wait for the 100,000 mi. point before dropping my transmission pan. (That's maybe 3 more years). Just for curiosity: (1) what was the color of the transmission fluid when you first drained it? (2) how would you describe the material on the mesh screen when you replaced it (e.g., grey powder, metal shavings, etc.)? Do you think you could have just cleaned the mesh screen?

UNOHOO

iTrader: (3)

the old fluid was kind of a chocolate brown, and smelled of burnt...ness lol, just smelled burnt, you might be able to clean out the wire screen but honestly i would just go buy the filter replacement kit, it was just a little over 20 bucks for the best one offered by advance auto parts, they did have to order it for me from another store which took several days so make sure you order it at least a few days before you plan do drop it, also just so you are aware, other than OEM atf from the stealership i couldnt find anyone that carried atf for our cars around here AND I LIVE 5 MIN FROM THE DC BELTWAY!! so i ordered mobil atf 3309 from here: http://avlube.com/mobilatf3309.html

just follow the DIY guide and you shouldnt have any problems at all, one thing he doesnt mention in the DIY and im not even entirely sure its necessary but my gfs dad (who was supervising) instructed me to put a little bit of some sealant under the gasket, mainly to hold it in place when i put the pan back up but also to prevent leaks and i also had to really really clean off sealant from the pan and block that the pan connects to to make sure i got a good seal, im guessing mine had been dropped before and the guys that put it on before used A LOT, the hardest part was just getting the pan to drop after all the bolt were taken out, had to use a small crowbar and screwdrivers whaomp whaomp waaaaaaaaaa, but everything is good to go now, shifts better and everything, im pleased

UNOHOO

iTrader: (3)

oh yea, material on the magnets (didnt really look at the screen too much) was more like wet powder with a few tiny tiny metal slivers but mainly wet metal powder

lexus114

Probably nothing if your not having any symptoms,Hopefully you will just find normal wear.

ToyotaLexus

does the RX300 take GL-4 or GL-5 gear oil? (or is no difference between the two?)

thanks!

Lexmex

GL-5 (this can be verified in the service manual, too).

UNOHOO

iTrader: (3)

just out of curiosity what is that rating? like viscosity or.....

Lexmex

It's an 85W90 for the RX300, but don't concern yourself with that, a good 75W90 synthetic is the way to go.

UNOHOO

iTrader: (3)

cool deal man, thats next on my list, i swear ever since i got on this site my car has never run better, thanks guys

ToyotaLexus

I decided it was too messy for me...

so I brought my Rx300 to the dealer, after the service advisor quoted me $95 to change both the rear diff fluid and the transfer case fluid. (plus sales tax of a few dollars)

while I was standing there waiting for the service advisor to write up the repair order, I noticed that the parts dept had the Mobil 1 synthetic gear 75w90 oil on the shelves(next to the Mobil 1 synthetic engine oils). I asked him how much more it is to get the synthetic, instead of whatever Toyota gear oil they used. The advisor said that they're not allowed to use synthetic gear oil on the RX(old or the new ones). The synthetic is only to be used on the ES/GS/IS/LS, as well as the LX. ???? I became confused... it was the first time that a Lexus dealer turned down my offer to pay more money for synthetic stuff....

He said that if I had a GS, for example, it would cost an extra $25 if I want to use the synthetic gear oil. (I've dealt with this same service advisor for almost 8 years)

can anybody tell me why my Lexus dealer didn't want my money? I thought synthetic was always better than conventional gear oil, no?

carguy07

Just a guess, but the early RX300's had limited slip differentials. Lexus probably told dealers not to put anything but the OE oil in them worried about the LSD additive (or lack of). The newer models are probably not using LSD so it's not an issue. The dealer probably never changed their rules for the RX not knowing what the reason was in the first place.

If there were real issues with synthetics in these cars they would be known by now. IMO

Lexmex

Go somewhere else or DIY, don't buy into that. I haven't had a single issue nor any else I have know with using the 75W90 synthetic oil. Granted 75W90 is not 85W90, but works just the same. Synthetic oil will be the only thing going into my RX300.

Lexmex

I haven't heard of any such TSB for the transfer case. What I do know of is that some people (myself included) had reported having issues with leaking transfer cases at the seals. However, this was BEFORE anyone had made any switchover from anything but the OEM 85W90 oil. So, why would Lexus want to continue down the same road?

When I did my transmission work last year, my uncle switched out the transfer case seals at that time, but still working on Pennzoil Synthetic 75W90 and not a leak since.

Unless I am missing something here, I don't remember anyone who has used 75W90 synthetic (Mobil 1, Amsoil, Royal Purple, I think a few went Redline) who have had leaks). I also recall a few people here over the years even took bottles of M1 75W90 to the dealer and didn't run into any issue.